All Molecules Have a Combination of Kinetic and Potential Energy

All molecules have a combination of kinetic and potential energy. If an external heat source were used to increase the kinetic energy of a group of molecules, the potential energy of the group would

A) decline because the sum of kinetic and potential energy always equals 100 percent.
B) be unaffected because no changes in the bonding pattern of the molecule had taken place.
C) also increase because potential and kinetic energy are directly proportional to one another.
D) It is not possible to predict the result using the information provided.